<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>
  <script>
    let i = 1
    let sum = 0
    // while (i <= 100) {
    //   document.write(`第${i}个<br>`)
    //   i++
    // }

    // while (i <= 100) {
    //   sum += i
    //   i++
    // }
    // document.write(`和为${sum}`)

    while (i <= 100) {
      if (i % 2 === 0) {
        sum += i
      }
      i++
    }
    document.write(`偶数和为${sum}`)
  </script>
</body>

</html>